Improvement in hoese hay-foeks



- A. COATES.

Horse Hay-Fork.

Patented Nov. 19, 1867.

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ABRAHAM COATES, OF WATERTOWN, NEW YORK.

Letters Patent No. 71,137, dated November 19, 1867. i

IMPROVEMENT IN HORSE HAY-FORKS.

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TO WHOM IT MAY CONCERN:

Be it known that I, ABRAHAM OOATES,Of Watertown, in the county ofJefferson, and State of New York, have invented certain new and usefulImprovements in HayForks; and I hereby declare the following to be afull, clear, and exact description of the same, reference being had tothe accompanying drawings.

My invention relates to that class of hay-fprks known as harpoon-forks,in which the claws for holding the hay are operated by means of acentre-bar working within a sheath of tubular or other suitable form.The claws, whether pivoted to the sheath or to the centre-bar,,arccaused to project from the sheath by the downward movement of thecentre-bar,- which, pressing or bearing upon their inner ends, throwsthe claws out from the sheath. Under this arrangement each claw may beconsidered to be a. lever, whose fulcrum is the point where itissupported by or pivoted to the sheath; that portion of it which projectsfrom the sheath constituting the longer arm, and that part on the otherside of the pivot, or, in other words, its inner end, upon which thebase of the centre-bar presses, the shorter arm of the lever.

The defects which it is the object of my invention to obviate arise fromthe ordinary method of combining the claws with the centre-bar and thecentrc-bar with the mechanism for looking or holding it in position.Under this method, when the fork is loaded, the, claws sustaining aweight of eight or ten hundred pounds of hay, for instance, the strainupon the centre-bar and locking mechanism is very great. The inner endof each claw constituting, as above explained, the shorter arm of alever, lies under the base of the centre-bar and presses forciblyagainst it, tending to force such bar upward in the sheath. If, as isusually the case, the outer ends of the claws or longer arms of thelevers have three orfour times the length of the inner ends, the upwardpressure upon the centre-bar, exerted by the shorter arms of the claws,will be proportionately increased; so

that if such claws support a weight of one thousand pounds, the innerends of the claws will be forced up against the base of the centre-barwith a pressure of two or three thousand pounds, or even more. Thelocking mechanism; whose function it is to resist this pressure, musttherefore be made extremely strong, and even then the bolts or othermechanism by which the bar is held in position are apt to be soon brokenor injured so as to be unfit for use. And in every event, such is thepressure and strain brought to bear upon the mechanism that the parts ofwhich it is composed become jammed together, and are held so tightly inthe centre-bar and sheath as to be with difficulty operated to releasethe bar when the load is to be dropped. The sheath and bar also receivea great part of the strain, and, as experience has shown, are frequentlyinjured and unfitted for use from this cause.

In order to obviate these difficulties, I combine with claws pivoted tothe sheath, a centre-bar, whose lower end is wedge-shaped or hasinclining faces converging, so as to form an angle which may be more orless acute, as desired. The claws and centre-bar are so combined thatwhen the former are projected from the sheath, the wedge-shaped end willlie between the claws, whose inner ends are so shaped as to fit and bein entire contact with the inclined faces of the bar. In this positionthe upward pressure upon the bar is greatly reduced, as

will be readily understood. If, for instance, the portion of the barheld between the ends of the claws were square, and the ends werecorrespondingly shaped, so as to fit upon each side of thebar, thenthere would be no upward pressure upon the latter, the inner ends of theclaws constituting, in effect, a pair of jaws which would grasp the bartightly, their hold upon it increasing with the weightcarried by thefork. This arrangement is open to the obvious objection thatconsiderable power must be applied to draw out the bar from between theclaws, and is only mentioned to illustrate more fully the nature of myinvention. Now, by making the part of the bar which lies between theclaws wedge-shaped instead of square, giving at the same time acorresponding bevel to the ends of the claws, it will be seen that whilethe claws are forced in opposite directions against the sides of thebur, so as to neutralize in a great degree the pressure exerted by each,there will be at the same time a slight upward pressure upon the bar,due to the inclination given the wedge-shaped end. By making the angleof inclination of the sides of such size as to'inducc an upward pressurejust suihcient tostart thc'bar when it is unlocked, the strain upon thelocking mechanism is reduced to the lowest possible point, and theliability of the operative parts-of the fork to be injured from thecause above mentioned is wholly obviated.

To enable others to fully understand and use my-invcntion, I willproceed to describe the manner in which the same is or may be carriedinto effect, by reference to the accompanying drawings, in which--Figures 1 and 2 are vertical central sections of a fork constructed inaccordance with my invention, and

Figure 3 is a side elevation of the centre-bar A represents the sheathofthe fork. B B are the claws pivoted to the sheath within slots at a,formed in the lower end of the same in the usual manner. Neither theseslots nor the claws pivoted within them are diametrically opposite eachother, the latter being so placed that when in the position shown infig. 1, their upper ends will lie partly side by side. 0 is thecentre-bar, of rectangular form, which moves up and down Within thelower portion 6 of the sheath, by which it is steadied and guided. l j'is the connecting-rod or link, hinged or pivoted at one end to thecentre-bar, and at the other to the locking mechanism. E is the lever bywhich the centre-basis operated, through the medium-of theconnecting-rod D, the upper end of which is pivoted to theoinner andshorter arm of the lever. F is the catch-by which the lever is held inposition when the centresbar is depressed, so as to project the clawsfrom the sheath. The claws B, which are pivoted separately to. and uponopposite sides of the sheath, havetheir inner ends bevelled or inclined,as shown at 0.0, so as to flt the wedgevshaped portion of the centre-barwhich is forceddown between them. The claws are also recessed at cl (Z,for the purpose hereinafter mention-ed. The centre-bar has a slot, e, ofsuitable width to receive the ends of the claws formed in it near itslower end. That portion of the bar immediately above the slot iswedge-shaped, the inolination of the faces ff corresponding to that ofthe claws at c c. The remaining part I; of the bar below the slot isrounded, or has a curved form, corresponding in somedegree to the curvedrecess d in the claws. The position of the centre-bar with relation tothe claws is such that when the latter are within the sheath, as. shownin fig. 1,'their upper ends will lie within the slot-e, while the parthwill be in the recesses (Z formed in the claws.

Oonfining attention to this part of the fork, it will be seen that ifthe centre-bar be depressed its rounded end 7L will strike against thelower edges of the recesses d, thus moving apart the lower ends of theclaws. The object of this is to start the movement of the claws, whichis'eontinued, by means of the wedgef pressing down between the ends 0,until the claws are fully projected from the sheath, as shown in fig. 2,the inclined 'faces of the bar, when in this position, being heldbetween the correspondingly-inclined ends of the claws.

For the reasons hereinbefore given, the tendency of the claws to liftthe bar or press it upwards within the sheath is thus greatly reduced,growing less in proportion to the increased aouteness of the angleformed\ by the inclined sides, so that by giving the parts the formshown in the drawing the force with which the bar is pressed upward maybe made just sufiicient to raise it from its position between the claws.This, of course, relieves the other parts of the fork from all strain,and admits of the locking mechanism being simply con- Btructed andreadily operated.

To the upper part of the sheath is attached the mechanism bywhich thecentre-bar is operated. I The lever E, which is connected, as beforeexplained, with the centre-bar by the hinged connecting-rod D', ispivoted to the sheath at 1. Its shorter arm d, which is curved or'standsat an angle to the inner part of the lever, extends within the sheath,and isconnected with the rod D by a hinge-joint. The longer arm at is onthe exterior of the sheath, and has a slot, 7:, of suitable dimensions,formed in it, through which plays, the end of a catch or detent, F. Thisdetent is pivoted to the sheath just above the lever, and, by means ofa, plate-spring, Z, the end of which rests against a shoulder, l, formedin its rear end, is pressed forward or downward, so that when the leveris raised, in the position shown in fig. 2, the notch in of the detentwill fit over the shoulder at at the; lower end of the slot is. Thelever is thus held in an upright position; and as there is, as beforestated, no excessive upward pressure upon the centre-bar andconnecting-rod, the detent and lever which it holds are subjected to nostrain, and can be operated with perfect case.

When the lever is in the position shown in fig. 2, its shorter arm isswung down within the sheath, thus causing the consequent depression ofthe centre-bar and the projection of the claws from the sheath. Inorder, therefore, to retract the centre-bar, the detent must be raised,so as to unlock the lever and allow its longer arm a? to be drawn down.To accomplish this, I attach to the .end of the detent, at o, a cord orrope, which passes up over a pulley, s, swivelled to the end of thelever, and thence extends downwarda suitable distance, so as to bewithin reach of the operator. v By pulling on the rope it will be seenthat the two operations, of raising the catch and drawing down the arm dare accomplished simultaneously. When the centre-bar is; withdrawn frombetween the claws the locking mechanism will be in the positionrepresented in fig. 1.

It is obvious that the wedge-shaped endf of the centre-bar can be usedeither with or without the auxiliary part It, and that the centre-barneed not be slotted at ,e, as shown in fig. 3. Its construction can bevaried in many particulars, so long as that portion which is forcedbetween the ends of the claws, when'the same are projected from thesheath, has the wedge-like formation hereinbefore explained.

Having now described my invention, and the manner in which the same isor may be carried. into eii'ect, what I claim, and desire to secure byLetters Patent, isa 1. In hay-forks, such as described, the combinationof a centre-bar, wedge-shaped or provided with inclined sides, asspecified, with claws or barbs pivoted to the sheath of the fork, andprovided with correspondingly inclined or bevelled ends, under such anarrangement that when the said claws are projected from the sheath theinclined sides of the centre-bar will be held between the said ends ofthe claws, in the manner and-for the purposes hcreinbefore stated. I p

2. The combination with the slotted centre-bar, -and wedges formedtherein, oi the claws or barbs pivoted to the sheath of the fork, andconstructed and arranged for operation'as herein described.

3. The combination, with the centre-bar and claws and hingedconnecting-rod, of tho leverto the shorter. arm of which said rod ispivoted, and the detent or locking device, under the arrangement and foroperation as herein shown and set forth. i

'4. The combination, with the lever for operating the centre-bar andclaws, oi the detent or locking device and its spring, under thearrangement specified, so that both the said lever and the detent bywhich it is held .in position may be actuated simultaneously'and at oneoperation, as set forth.

In testimony whereof I have signedamy name this specification before twosubscribing witnesses.

ABM. OOATES. Witnesses:

M. BAILEY, G. S. PAGE, Jr.

